loadmodule "luaiup"
loadmodule "luahandle"
loadmodule "lualibs"

load "iupe-dbuffer.lua"

if not iupe then iupe = {} end
if not iupep then iupep = {} end

local cursorcolors = {
    GREEN = cd.EncodeColor(0, 224, 0),
    LIGHTGREEN = cd.EncodeColor(224, 255, 224),
}

local mousecolors = {
    YELLOW = cd.EncodeColor(255, 255, 0),
    LIGHTYELLOW = cd.EncodeColor(255, 255, 192),
}

markercolors = {
    [-2] = cursorcolors.GREEN,
    [-1] = mousecolors.YELLOW,
    [0]  = cd.EncodeColor(0, 255, 178), -- 0.45
    [1]  = cd.EncodeColor(0, 255, 255), -- 0.50
    [2]  = cd.EncodeColor(0, 178, 255), -- 0.55
    [3]  = cd.EncodeColor(0, 102, 255), -- 0.60
    [4]  = cd.EncodeColor(0, 25, 255),  -- 0.65
    [5]  = cd.EncodeColor(50, 0, 255),  -- 0.70
    [6]  = cd.EncodeColor(127, 0, 255), -- 0.75
    [7]  = cd.EncodeColor(204, 0, 255), -- 0.80
    [8]  = cd.EncodeColor(255, 0, 229), -- 0.85
    [9]  = cd.EncodeColor(255, 0, 152), -- 0.90
    [10] = cd.EncodeColor(255, 0, 76),  -- 0.95
}

iupep.hexview = {
    gridsize = { x = 8, y = 14 },
    
    printgrid = function (self, msg, y, x)
        local cvdb = self.cvdb
        if not x then x = self.textcursor.x end
        if not y then y = self.textcursor.y end
        cvdb:Foreground(cd.BLACK)
        cvdb:Text(x * self.gridsize.x, self.height - self.gridsize.y * (y + 1), msg)
        self.textcursor.x = x + msg:len()
        self.textcursor.y = y
    end,
    
    colorgrid = function (self, color, len, y, x, height)
        local cvdb = self.cvdb
        if not len then len = 1 end
        if not height then height = 1 end
        if not x then x = self.textcursor.x end
        if not y then y = self.textcursor.y end
        cvdb:Foreground(color)
        local xmin, xmax, ymin, ymax = x * self.gridsize.x, (x + len) * self.gridsize.x - 1, self.height - self.gridsize.y * (y + 1 - height) - 2, self.height - self.gridsize.y * (y + 1) - 1
        cvdb:Box(xmin, xmax, ymin, ymax)
    end,
    
    byte2char = function(self, b)
        if b >= 32 and b <= 127 then
            return string.char(b)
        else
            return "."
        end
    end,

    draw = function (self)
        local cvdb = self.cvdb
        if not cvdb then return iup.DEFAULT end
        cvdb:Clear()
        local handle = self.handle
        local filecursor = self.filecursor + 0
        local nbbytes = self.nbbytes + 0
        local filesize = self.filesize + 0
        local oldfilecursor = self.oldfilecursor + 0
        local buf = self.buf
        local max_bytes = math.max(math.min(filesize - filecursor, nbbytes), 0)
        local old_max_bytes = (self.old_max_bytes or -1) + 0
        if handle then
            handle:seek(filecursor)
            if ((filecursor ~= oldfilecursor or max_bytes ~= old_max_bytes) and max_bytes ~= 0) or not buf then
                if buf then buf:destroy() end
                buf = Buffer(true)
                self.buf = buf
                handle:copyto(buf, max_bytes)
                self.oldfilecursor = filecursor
                self.old_max_bytes = max_bytes
            else
                buf:seek(0)
            end
        end
        local line = 0
        local rcursor = 0
        local b
        local kline, kcolumn
        local mline, mcolumn
        local krcursor = self.kcursor - filecursor
        local mrcursor = self.mcursor - filecursor
        local columns = self.columns + 0
        local nblines = self.nblines + 0
        kline = math.floor(krcursor / columns)
        kcolumn = krcursor % columns
        mline = math.floor(mrcursor / columns)
        mcolumn = mrcursor % columns

        if self.mcursor ~= "-1" then
            self:colorgrid(mousecolors.LIGHTYELLOW, 12 + columns * 4, mline, 0)
            self:colorgrid(mousecolors.LIGHTYELLOW, 2, nblines - 1, mcolumn * 3 + 10, nblines)
            self:colorgrid(mousecolors.LIGHTYELLOW, 1, nblines - 1, mcolumn + 12 + columns * 3, nblines)
            self:colorgrid(mousecolors.YELLOW, 2, mline, mcolumn * 3 + 10)
            self:colorgrid(mousecolors.YELLOW, 1, mline, mcolumn + 12 + columns * 3)
        end

        self:colorgrid(cursorcolors.LIGHTGREEN, 12 + columns * 4, kline, 0)
        self:colorgrid(cursorcolors.LIGHTGREEN, 2, nblines - 1, kcolumn * 3 + 10, nblines)
        self:colorgrid(cursorcolors.LIGHTGREEN, 1, nblines - 1, kcolumn + 12 + columns * 3, nblines)
        self:colorgrid(cursorcolors.GREEN, 2, kline, kcolumn * 3 + 10)
        self:colorgrid(cursorcolors.GREEN, 1, kline, kcolumn + 12 + columns * 3)
        
        local marker, len, mlen
        for i = 0, 10 do
            marker = self.markers[i] or -1
            marker = marker - filecursor
            mlen = self.markerslengths[i]
            if marker >= 0 and self.showmarkerslengths and mlen and mlen > 0 then
                len = math.min(mlen, nbbytes - marker)
            elseif marker >= 0 and marker < nbbytes then
                len = 1
            else
                len = 0
            end
            for j = 1, len do
                mline = math.floor(marker / columns)
                mcolumn = marker % columns
                self:colorgrid(markercolors[i], 2, mline, mcolumn * 3 + 10)
                self:colorgrid(markercolors[i], 1, mline, mcolumn + 12 + columns * 3)
                marker = marker + 1
            end
        end
        
        while rcursor < max_bytes do
            local dstring = ""
            self:printgrid(hex(buf:tell() + filecursor, "%08x  "), line, 0)
            for c = 1, columns do
                b = buf:readU8()
                self:printgrid(hex(b, "%02x "))
                dstring = dstring .. self:byte2char(b)
                rcursor = rcursor + 1
                if rcursor >= max_bytes then break end
            end
            self:printgrid(dstring, line, 12 + columns * 3)
            line = line + 1
        end
        
        cvdb:Flush()
        
        return iup.DEFAULT
    end,
    
    updatescrollbar = function (self)
        self.ymax = math.floor(self.filesize / self.columns)
        self.dy = 1
        self.posy = math.floor(self.filecursor / self.columns)
        iup.Update(self)
    end,
    
    resize_cb = function (self, width, height)
        local displaylines = self.displaylines + 0
        self.nblines = displaylines > 0 and displaylines or math.floor(height / self.gridsize.y)
        self.nbbytes = self.nblines * self.columns
        self:updatescrollbar()
        iupep.dbuffer.resize_cb(self, width, height)
    end,

    keypress_cb = function (self, c, press)
        if press == 0 then return iup.DEFAULT end
        local kaction = false
        local raction = false
        local kcursor = self.kcursor + 0
        local columns = self.columns + 0
        local filesize = self.filesize + 0
        local filecursor = self.filecursor + 0
        local nbbytes = self.nbbytes + 0
        if c == iup.K_UP then
            kaction = true
            kcursor = math.max(kcursor - columns, 0)
        elseif c == iup.K_DOWN then
            kaction = true
            kcursor = math.min(kcursor + columns, filesize - 1)
        elseif c == iup.K_LEFT then
            kaction = true
            kcursor = math.max(kcursor - 1, 0)
        elseif c == iup.K_RIGHT then
            kaction = true
            kcursor = math.min(kcursor + 1, filesize - 1)
        elseif c == iup.K_PGUP then
            kaction = true
            kcursor = math.max(kcursor - nbbytes + columns, 0)
        elseif c == iup.K_PGDN then
            kaction = true
            kcursor = math.min(kcursor + nbbytes - columns, filesize - 1)
        elseif c == iup.K_HOME then
            kaction = true
            kcursor = kcursor - (kcursor % columns)
        elseif c == iup.K_END then
            kaction = true
            kcursor = math.min(kcursor + columns - (kcursor % columns) - 1, filesize - 1)
        elseif c == iup.K_cUP then
            kaction = true
            if filecursor - columns >= 0 then
                kcursor = kcursor - columns
                filecursor = filecursor - columns
            end
        elseif c == iup.K_cDOWN then
            kaction = true
            if filecursor + columns < filesize then
                kcursor = kcursor + columns
                filecursor = filecursor + columns
            end
        elseif c == iup.K_cLEFT then
            kaction = true
            kcursor = math.max(kcursor - 1, 0)
            filecursor = math.max(filecursor - 1, 0)
        elseif c == iup.K_cRIGHT then
            kaction = true
            kcursor = math.min(kcursor + 1, filesize - 1)
            filecursor = math.min(filecursor + 1, filesize)
        elseif c == iup.K_cPGUP then
            kaction = true
            if filecursor - nbbytes >= 0 then
                kcursor = math.max(kcursor - nbbytes, 0)
                filecursor = math.max(filecursor - nbbytes, 0)
            end
        elseif c == iup.K_cPGDN then
            kaction = true
            if filecursor + nbbytes < filesize then
                kcursor = math.min(kcursor + nbbytes, filesize - 1)
                filecursor = math.min(filecursor + nbbytes, filesize)
            end
        elseif c == iup.K_cHOME then
            kaction = true
            kcursor = 0
        elseif c == iup.K_cEND then
            kaction = true
            kcursor = filesize - 1
        elseif c == iup.K_mLEFT then
            raction = true
            columns = columns - 1
        elseif c == iup.K_mRIGHT then
            raction = true
            columns = columns + 1
        elseif c == iup.K_mUP then
            raction = true
            filecursor = math.max(filecursor - columns, 0)
        elseif c == iup.K_mDOWN then
            raction = true
            filecursor = math.min(filecursor + columns, filesize)
        elseif c == iup.K_mPGUP then
            raction = true
            filecursor = math.max(filecursor - nbbytes, 0)
        elseif c == iup.K_mPGDN then
            raction = true
            filecursor = math.min(filecursor + nbbytes, filesize)
        elseif c == iup.K_1 then
            kaction = true
            local m = self.markers[1]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_2 then
            kaction = true
            local m = self.markers[2]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_3 then
            kaction = true
            local m = self.markers[3]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_4 then
            kaction = true
            local m = self.markers[4]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_5 then
            kaction = true
            local m = self.markers[5]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_6 then
            kaction = true
            local m = self.markers[6]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_7 then
            kaction = true
            local m = self.markers[7]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_8 then
            kaction = true
            local m = self.markers[8]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_9 then
            kaction = true
            local m = self.markers[9]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_0 then
            kaction = true
            local m = self.markers[10]
            if m ~= -1 then
                kcursor = m
            end
        elseif c == iup.K_m1 then
            kaction = true
            self.markers[1] = kcursor
        elseif c == iup.K_m2 then
            kaction = true
            self.markers[2] = kcursor
        elseif c == iup.K_m3 then
            kaction = true
            self.markers[3] = kcursor
        elseif c == iup.K_m4 then
            kaction = true
            self.markers[4] = kcursor
        elseif c == iup.K_m5 then
            kaction = true
            self.markers[5] = kcursor
        elseif c == iup.K_m6 then
            kaction = true
            self.markers[6] = kcursor
        elseif c == iup.K_m7 then
            kaction = true
            self.markers[7] = kcursor
        elseif c == iup.K_m8 then
            kaction = true
            self.markers[8] = kcursor
        elseif c == iup.K_m9 then
            kaction = true
            self.markers[9] = kcursor
        elseif c == iup.K_m0 then
            kaction = true
            self.markers[10] = kcursor
        elseif c == iup.K_c1 then
            kaction = true
            self.markers[1] = nil
        elseif c == iup.K_c2 then
            kaction = true
            self.markers[2] = nil
        elseif c == iup.K_c3 then
            kaction = true
            self.markers[3] = nil
        elseif c == iup.K_c4 then
            kaction = true
            self.markers[4] = nil
        elseif c == iup.K_c5 then
            kaction = true
            self.markers[5] = nil
        elseif c == iup.K_c6 then
            kaction = true
            self.markers[6] = nil
        elseif c == iup.K_c7 then
            kaction = true
            self.markers[7] = nil
        elseif c == iup.K_c8 then
            kaction = true
            self.markers[8] = nil
        elseif c == iup.K_c9 then
            kaction = true
            self.markers[9] = nil
        elseif c == iup.K_c0 then
            kaction = true
            self.markers[10] = nil
        elseif c == iup.K_SP then
            kaction = true
        end
        if kaction then
            while kcursor < filecursor do filecursor = filecursor - columns end
            while (kcursor - filecursor) >= nbbytes do filecursor = filecursor + columns end
            filecursor = math.min(math.max(filecursor, 0), filesize)
            self.kcursor = kcursor
            self.filecursor = filecursor
            self.columns = columns
            self:setcursor()
            return iup.IGNORE
        end
        if raction then
            self.filecursor = filecursor
            self:updatescrollbar()
            self:updatecolumns(columns)
            self:draw()
            return iup.IGNORE
        end
        return iup.DEFAULT
    end,
    
    updatehandle = function (self, handle)
        self.handle = handle
        local filesize = handle and handle:getsize() or 0
        if filesize < 0 then self.handle = nil filesize = 0 end
        self.filesize = filesize
        self.old_max_bytes = -1
        self.old_filecursor = -1
        self:updatescrollbar()
        self:draw()
        for _, v in ipairs(self.cbs) do
            v.cb(v.opaque, self, true)
        end
    end,
    
    map_cb = function (self)
        iupep.dbuffer.map_cb(self)
        local cvdb = self.cvdb
        if not cvdb then return iup.DEFAULT end
        cvdb:Font("Courier", cd.PLAIN, -self.gridsize.y)
        -- self.rastersize = (self.gridsize.x * (self.columns * 4 + 14)) .. "x" -- will not allow the control to be shrinked.
        -- self.gridsize.x = cvdb:GetFontDim() -- doesn't work as expected
    end,
    
    setcursor = function (self, markerid, value)
        if markerid then
            markerid = markerid + 0
            if markerid >= 0 and markerid <= 10 then
                self.markers[markerid] = value + 0
            elseif markerid == -2 then
                self.kcursor = value + 0
                self:keypress_cb(iup.K_SP, 1)
            end
        end
        for _, v in ipairs(self.cbs) do
            v.cb(v.opaque, self)
        end
        self:updatescrollbar()
        self:draw()
    end,
    
    registercb = function (self, cb, opaque)
        table.insert(self.cbs, { cb = cb, opaque = opaque })
    end,
    
    wheel_cb = function (self, delta, x, y, status)
        if delta > 0 then
            for i = 1, delta do self:keypress_cb(iup.K_cPGUP) end
        else
            for i = 1, -delta do self:keypress_cb(iup.K_cPGDN) end
        end
    end,
    
    scroll_cb = function (self, op, posx, posy)
        if op == iup.SBUP then
            self:keypress_cb(iup.K_mUP, 1)
        elseif op == iup.SBDN then
            self:keypress_cb(iup.K_mDOWN, 1)
        elseif op == iup.SBPGUP then
            self:keypress_cb(iup.K_mPGUP, 1)
        elseif op == iup.SBPGDN then
            self:keypress_cb(iup.K_mPGDN, 1)
        else
            local columns = self.columns + 0
            local startoffset = self.filecursor % columns
            self.filecursor = math.min(math.max(math.floor(self.posy) * columns + startoffset, 0), self.filesize)
            self:draw()
        end
        return iup.DEFAULT
    end,
    
    motion_cb = function (self, x, y, status)
        local r = self:resolvepos(x, y)
        if r ~= -1 then self.mcursor = r end
        self:setcursor()
        return iup.DEFAULT
    end,
    
    resolvepos = function (self, x, y)
        local line = math.floor(y / self.gridsize.y)
        local column = math.floor(x / self.gridsize.x)
        local filecursor = self.filecursor + 0
        local columns = self.columns + 0
        
        -- offset display
        if column <= 7 then
            return filecursor + columns * line
        end
        
        -- gap 1
        if column <= 9 then return -1 end
        
        -- hex display
        if column <= (columns * 3 + 10) then
            -- interhex gap
            if (column - 10) % 3 == 2 then return -1 end
            return math.floor((column - 10) / 3) + filecursor + columns * line
        end
        
        -- gap 2
        if column <= (columns * 3 + 11) then return -1 end
        
        -- ascii display
        if column <= (columns * 4 + 11) then
            return column - columns * 3 - 12 + filecursor + columns * line
        end
        
        return -1
    end,
    
    button_cb = function (self, button, pressed, x, y, status)
        if pressed == 1 then return iup.DEFAULT end
        if button == iup.BUTTON1 then
            local newpos = self:resolvepos(x, y)
            if newpos ~= -1 then
                self.kcursor = newpos
                self:setcursor()
                return iup.IGNORE
            end
        elseif button == iup.BUTTON3 then
            local newpos = self:resolvepos(x, y)
            if newpos ~= -1 then
                self.markers[0] = newpos
                self:setcursor()
                return iup.IGNORE
            end
        end
        return iup.DEFAULT
    end,
    
    updategridsize = function (self, gridsize)
        self.gridsize = gridsize or iupep.hexview.gridsize
        self:resize_cb(self.width, self.height)
    end,
    
    updatecolumns = function (self, columns)
        self.columns = columns or 16
        self:resize_cb(self.width, self.height)
    end,

    create = function (tab)
        local handle = tab.handle
        local columns = tab.columns
        local gridsize = tab.gridsize
        tab.handle = nil
        tab.columns = nil
        tab.gridsize = nil
        tab.cursor = "TEXT"
        tab.expand = "Yes"
        tab.border = "No"
        tab.minsize = "0x0"
        tab.size = "0x0"
        tab.scrollbar = "vertical"
        local r = iup.canvas(tab)
        r.action = iupep.dbuffer.action
        r.draw = iupep.hexview.draw
        r.resize_cb = iupep.hexview.resize_cb
        r.keypress_cb = iupep.hexview.keypress_cb
        r.button_cb = iupep.hexview.button_cb
        r.map_cb = iupep.hexview.map_cb
        r.unmap_cb = iupep.dbuffer.unmap_cb
        r.scroll_cb = iupep.hexview.scroll_cb
        r.motion_cb = iupep.hexview.motion_cb
        r.wheel_cb = iupep.hexview.wheel_cb
        r.printgrid = iupep.hexview.printgrid
        r.colorgrid = iupep.hexview.colorgrid
        r.updatehandle = iupep.hexview.updatehandle
        r.updategridsize = iupep.hexview.updategridsize
        r.updatecolumns = iupep.hexview.updatecolumns
        r.updatescrollbar = iupep.hexview.updatescrollbar
        r.resolvepos = iupep.hexview.resolvepos
        r.setcursor = iupep.hexview.setcursor
        r.registercb = iupep.hexview.registercb
        r.byte2char = iupep.hexview.byte2char
        r.cbs = {}
        r.handle = handle
        r.columns = columns or 16
        r.filecursor = 0
        r.oldfilecursor = -1
        r.kcursor = 0
        r.filesize = handle and handle:getsize() or 0
        r.mcursor = -1
        r.markers = {}
        r.markerslengths = {}
        r.showmarkerslengths = false
        r.displaylines = 0
        for i = 0, 10 do r.markers[i] = -1 end
        r.gridsize = gridsize or iupep.hexview.gridsize
        r.textcursor = { x = 0, y = 0 }
        return r
    end,
}

iupe.hexview = iupep.hexview.create